In her beautifully articulated, extremely wise play now at Off-Broadway’s Atlantic Theatre Company, Blue Ridge, perhaps Abby Rosebrock doesn’t intend to question the essential tenets of the support-group movement. Or perhaps that is her intention — I don’t know. What I do know is that the idea of 12-step programs as safe havens in “safe houses” gets a vigorous shake-up before her two tense acts shudder to an end.

The immediate focus is a religious-oriented safe house in the Blue Ridge Mountains of North Carolina. The makings of a damaging problem are already in place at St. John’s Service House, but the catalyst that makes it explode is the arrival of Alison (Marin Ireland), a nervous wreck.

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At this home for people in recovery, Alison doesn’t actually fit the category. For it wasn’t drinking that caused her dismissal as an English teacher from Blue Ridge High School but taking an axe to a car owned by the school’s head administrator. Who also happens to be Alison’s longtime, and evidently troubling, significant other, and married to someone else.

Eager to fit in at the safe house, Alison participates in her first Bible-study meeting with enthusiasm — as if she just got invited to the senior prom and can’t wait to choose her dress and receive her corsage. In addition to the organizer, Grace (Nicole Lewis), those in the group include Cherie (Kristolyn Lloyd), Wade (Kyle Beltran) and, later on, Pastor Hern (Chris Stack), the house’s co-founder.

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Rosebrock easily establishes the relationships between and among these characters. Grace and Hern, for example, are very committed to the house. With Cherie, Hern behaves as if he’s found an extramarital liaison more intellectually and romantically stimulating than with his (unseen) wife. Cherie responds to Hern with few misgivings. Wade, while getting along with Grace and Cherie, seems uncertain. He balks when Hern pressures him to shape up.

There’s also talk of Cole (Peter Mark Kendall), a new occupant who soon arrives. Walking through the front door of Adam Rigg’s appropriately Goodwill-ish set, he brings with him a set of distinct, but not fully diagnosed, neuroses.

As all six characters circle each other like caged animals, Rosebrock sets her plot going in an impressive blend of humor, pathos, theatrics, surprise and heady dramatic spice. She gives one character — Alison — the whip as self-appointed ringmaster. That whip leads to her undoing.

Alison concedes, and believes, that she has literally and figuratively buried the axe, but she hasn’t. Her unforgiving attitude toward men (they’re the downfall of women) is practically her life’s motivation. She seizes on what she interprets as Hern stringing Cherie along, and Cherie’s acquiescence, as something she can ameliorate by the benefit of her experience.

But Cherie maintains that she can handle herself without anyone’s interference. (The moral of Blue Ridge may be: better to let people make their own mistakes.) At a low moment, Alison turns to Cole. There’s an acknowledgment of something between them, and it only exacerbates Cole’s festering self-doubt.

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Interpersonal eruptions unfold and mount in increasingly incendiary scenes that underline Rosebrock’s command of psychological complexities. She creates numerous situations in which her characters are simultaneously sympathetic and alienating. Hern’s breakdown when there’s a change in the understanding between him and Cherie is one such. Another amusing, insightful sequence has Cole and Wade discussing the pros and cons of fellatio, though it’s called by another phrase. (At the performance I attended, why did more women than men laugh audibly at this? The answer eludes me.)

Rosebrock’s script receives first-rate direction from Taibi Magar, whose cast members are uniformly flawless. The crumbling authority displayed by Stack’s Hern is admirably subtle; Hern’s crying jag is totally unexpected. Lloyd deftly shows Cherie’s certainty as well as her uncertainty. Beltran’s growing mental stability as Wade is sure. The unsteady expressions worn by Kendall shows us the roiling fears inside of Cole. As Grace — the one self-assured occupant of the house — Lewis brings a proper empathetic weight.

Ireland’s Alison, however, is a revelation. Or it would be if her performances over the last couple of decades weren’t one revelation after another. Could she have improved on her Alma Winemiller in Tennessee Williams’s Summer and Smoke at Classic Stage Company? She needn’t, but, like her Alma, she’s eminently watchable while never sneaking attention from other players. The high points of Ireland’s Alison? They’re all high, but none higher than her treatment of a line late in Act I:

This is not rage, Pastor Hern — this is hatred.

Throughout Blue Ridge, music is heard. Cherie has The Supremes on her iPad. Wade plays guitar. Sound designer Mikaal Sulaiman give us country music at the start. During the play, Alison discourses on Carrie Underwood’s “Jesus, Take the Wheel,” leading to an impromptu singalong.

Yet the major song here is Rosebrock’s plaintive play. Its unflinching examination of an unsafe safe house could be read as a metaphor for frighteningly unsafe times.